Steam-engine-valve reversing gear



July 28, 1925.

J. G. BLUNT STEAM ENGINE VALVE REVERSING GEAR Filed Aug. 18, 1921 2 Sheets-Sheet l wrmsssas July 28,1925. "1,547,727

J. G. BLUNT STEAM ENGINE VALVE REVERSINGY GEAR Filed Aug. 18, 1921 2 Sheets-Sheet 2 WITNESSES I Awe 420:2

which improvement Patented July 28, 1925, a

UNITED JAMES e. BLUN'I, or SCHENECTADY, NEW-YORK.

, sT A vI-EN INE VAL E aEvnRsINGeEA-R.

Tofall whomitmay, co'ncemi'f f T Be it 'known :that I, JAMES G. BDUNT, of

Schenectady, 'in the county of Schenectady and State of NewYorkfhave inventeda certain new and useful Improvement in "steam-Engine valve Reversing Gears, of the following :is a =s;pecification.

My invention relates tothe general class or type'of reversing gears in which 'a' piston, working in a cylindnandactuated by fluid pressure, is applied :to effect the variation in position, and maintenance in adjusted position, of the valve gear of a steam engine, and its "object is to provide an appliance of such type, "in which a simplification and econom'ization of constructi'on will :be effected, and a {more positive operation at ta'ined,"by' the'provision of alunitary self contained structure," comprising all the working members for the appliance, which may be mounted on a single support and from which the floating lever m echanism ordinarily applied ifor'the control of the movements" of the gear 'sha'l'lbe eliminated. The improvement claimed is hereinafterfully set forth.

In the accompanyin'g'drawings: Figure 1 1s a d agrammatic sideview of a locomotive engine, illustrating the application *of ':my

invention in connection with a Walschaerts valve gear; Fig, 2, a side View, partly in section, of the reversing cylinder and its accessories, Fig. 3, an end view, partly in section, .011 the line a" as of Fig. 2 of' the same; Fig. 4 a longitudinal central section, on an enlarged scale, through the operating valve casing, and Fig. 5, a front view, of the same, with the cap removed.

Referring tofthe drawings, my invention, which is applicable in'connection with any of the various known types of distribution valve mechanism, it is illustrated Fig. "1, as applied .for the control o-f'a Wal'sc' haerts valve gear of the ordinary construction, which comprises a link, 1, eccentric rod, 1, combinationlever, '1", and'radius bar, 1, and

is coupled to 'a distribution valve stem, 1.

The radius bar is coupled to the lower arm, 2", of a reverse shaft, 2, and is raised and lowered throughits range of traverse on the link, 1,- by my improved reversing mechaappiiea'tion filed August? 1s, 1921. serial in). 493,368.

nism, hereinafter-described, which is-coupled to the :upper arm, 2 ,-of the reverse shaft.

In the practiceof my invention, refer-ring descriptively to the specific embodiment thereof which is herein exemplifiedfl provide, for the enclosure and support of all the working members of a reversing ;gear, a unltary structure, cornprisin a fluid pressure cylinder, 3; cross. head guides, 7 'Z, projecting longitudinally from one end thereof; a vertical standard, 8, fixed to,and extending above the guides; an operating Valve chest, 10, located at the top of said standard; and a segment support, 11, extending upwardly from. the valve chest.

Flanges, 7*, formed on the lower guide, 7,

adapt the structure to be bolted to supports located in any convenient. position below the cab, C, of the locomotive. The cylinder, 3, 'is closed, at its ends, -by heads, 3%, and is ifitted with a properly packed piston, 5, fixed on a piston rod, 5, which passes through a .stulfing box, 3 inthe forward head of the traverse on the guides, '7, and is coupled, by

faqpin, 6, to one end of a reach rod, 9, the opposite end of which is coupled to the upper arm, 2*, of the reverse shaft. The cyl- "inder and guides, are located below the cab,

C, of the locomotive, and the standard, '8,

"projects upwardly therefrom, into the cab,

so as to place the valve chest, l0, and hand lever, 13, which it carries, in convenient reach of the :engineman.

' The piston of the reversing cylinder. 3.

is actuated by fluid under pressure, which may be either steam from the boiler, A, of

the locomotive, supplied to the chest, 10, of

"the operating valve, through a pipe, 19, or compressed air, supplied from the main reservoir, .B, of "the; air brake mechanism, r=through a pipe, 19 The supply and exhaust of motive fluid .to and from theropposite ends of the reversing cylinder, 3, are effected through pipes, 20 20, leading from the operating valve chest, 10, to opposite ends; of the reversingcylinder, and are controlled by an operating ,valve, 12, fixed upon a stem, 12 rotatable about its axis in the valve chest, which is-closed by a removable cap, 10. :By movement of the valve about its axis, in one direction, as to the right, fluid pressure will be admitted to the left hand end of the cylinder, through'the pipe, 20, and will be exhausted from the right hand end, through the pipe, 20 the exhaust cavity of the valve, 12, the exhaust port, 10 of the valve chest, and the exhaust pipe 10, to the atmosphere. A reversal of the traverse of motive fluid to and from the opposite ends of the cylinder, will, of course, be effected, movement of the operating valve to the left. e 7

Movement, in either desired direction, is imparted to the operating valve by a hand lever, 13, which is journalled on the valve chest, 10, and is held in any adjusted position by'the engagement of a latch lever, 14, with one of a plurality of notches in a seg ment, 15, secured'to the segment support,11. A controlling rod, 16, is coupled, at its upper end, by a pin, 16*, to the hand lever, 13, and its lower end is fitted, with the capacity of relative longitudinal movement, in a block, 17 journalled on the cross head pin, 6. The controlling rod, 16 passes freely through a swivel, 18, which is journalled in a crank arm, 18, fixed on the stem, 12 of the operating valve,

In the operation of the reversing mechanism above described, when it is'desired to change the direction of movement of the 7 engine, or vary the point of cut off, which direction to said valve.

operations are elfected by adjustments of the radius bar, 1, relatively to the link, 1, the hand lever, 13, is unlatched from the segment, 15, and moved by the operator in the appropriate direction, and to the proper extent. This movement of the hand lever, swings the controlling rod, 16, about the axis of its fulcrum pin, 6 on the cross head, said rod, through its swivelling connection with the crank arm, 18, of the operating valve, 12, imparting movement, in the same Motive fluid is thereby admitted to the proper end of the reversing cylinder, 3, and exhausted from the opposite end thereof. This admission and exhaust of motive fluid eflt'ects the requisite movement of the piston, 5, and its attachments, and upon thecessation of movement of the hand lever, the controlling rod, 16, swinging upon the pin, 16 by which it is coupled to the hand lever, as a fulcrum, returns the operating valve, 12, to the same normal neutral or central position, thereby instituting and maintaining an equilibrium of pressure on opposite sides of the piston of the reversing cylinder, and holding the valve gear in its desired adjusted position.

In case an external force, such as may be exerted by undue friction in the distribution valve gear, should act on the piston, 5, through the reach rod, and its attachments, and cause the piston to move in either 'direction, the resultant movement of the controllingrod about the cross head pin, 6 as a fulcrum, will partially rotate the operating valve and automatically admit fluid pressure to the reversing cylinder, in opposite direction to that ofthe abnormal and undesired movement. Equilibrium of pressure, will thereby be established and maintained on opposite :sides of the piston, and further movement of the valve gear from adjusted position be prevented.

A substantial structural advantage is attained by my invention in the provision of a unitary self contained structure, in and by which all the moving members of thereversing mechanism are enclosed and supported, and which is adapted for application in a locomotice by connection to a single suitably located support, instead of a plurality of supports at diflerent positions, as in ordinary practice. operationof the mechanism by reason of the eliminationof variations or expanding conditions'between diflerent operating meme bers, and of the ordinary floating lever mechanism, will also be apparent to those familiar with the construction and operation of locomotive engines, as will be the advantage, in practice, of locating the operating valve and its hand lever, in the cab of the locomotive, where these members are protected from the weather, and the access of dust and grit, and" are immediately and readily accessible to the engineman.

I claim as my invention and desire to secure by Letters Patent:

1. A reversing gear for locomotive valve mechanism, comprising a power cylinder, connections therefrom to said mechanism including a reciprocatory cross-head, a rotary valve for said cylinder, a hand-lever pivotally mounted on the axis of said valve, a rod pivoted at one end on said lever and havin r a swinging and sliding connection with said cross-head, and a crank-arm onsaid valve having a swivel connection with said rod, whereby movement of said lever causes said rod to swing about its pivotal connection with said cross-head and to partially rotate said valve, whereupon motive fluid is ad- The more positive mitted to said cylinder,'the consequent movement of said cross-head swinging said rod about its pivotal connection with said lever to return said valve to closed position.

2. A reversing gear for locomotive valve mechanism, comprising a power cylinder, located beneath the cab, guides extending from one end of said cylinder, a cross-head on said guides, a standard on said guides, a valve casing on said standard, a valve rotatable in said casing to control the. supply of motive fluid to said cylinder, connections from said cross-head to said mechanism, a hand-lever pivoted on said casing coaxially with said valve and extending into the cab,

a rod pivoted to said lever and to i crosshead, and a swivel crank connection between cross-head swinging said rod about its said rod and said valve, whereby movement plvotal connectlon W1th sald lever to return of sald lever causes said rod to swlng about said valve to closed positlon.

its pivotal connection with said cross-head JAMES G. BLUNT. and to partially rotate said valve, where- Witnesses: I upon motive fluid is admitted to said cyl- E. I. SCHAUBER,

inder, the consequent movement of said JOHN L. STEELE. 

